Telephone system



Oct. 20, 2 1,557,642

G. A. YANQCHOWSKI TELEPHONE SYSTEM Filed June 20. 1921 fl agiflwi/hms'hJi? 7 A 27272777224;

Patented Oct. 20, 1925.

UNITED STATES PATENT OFFICE.

GEORGE A. YANOGHOVJSKI, OF CHICAGO, ILLINOIS, ASSIGNOR T0 KELLOGGSWITCH- BOARD AND SUPPLY QCEIFIP.AIEY, OI CHITAGO, ILLINOIS, ACORPORATION OF ILLI- NOIS.

TELEPHONE SYSTEM.

Application filed. June 20, 1921-.

To all whom it may concern:

Be it known that I, GEORGE A. YANG- onowsnr, a citizen of the UnitedStates of America, resident of Chicago, in the county of Cook and Stateof Illinois, haveinvented certain new and useful Improvements inTelephone Systems, of which the following is a specification.

My invention relates to telephone systems and has to domoreparticularlyrwith automatic ringing systems such as are provided foroperators cord circuits in which an interrupter relay is intermittentlyenergized and de-energized to intermittently apply ringing current tothe called line.

A feature of my invention is theprovision of an improved circuitarrangement whereby, should a' calling subscriber replace his receiverprior to receiving a response from a called substation a distinctivesignal is given to the operator that established the connection in theform of a flash ring signal, advising her that she should immediatelydisconnect the calling cord from the called line as the callingsubscriber has replaced his receiver. v

Another feature of my invention is the provision of a pair of ringinginterrupters in association with the usual interrupter relay, one beingof the ordinary interrupter type as commonly used in automatic ringingsystems for intermittently energizing and de-energizing the ringinginterrupter or flip flop relay to intermittently connect ringing currenttothe called line. The second interrupter is provided with a shortringing period and a comparatively long silent period and is alsorotated at a much slower speed than the ordinary interrupter. Thissignal is arranged to advise the called subscriber that the callingsubscriber has replaced his receiver. Means in association ivith thepair of interruptcrs are actuated when a callingfsubscriber replaces hisreceiver before receiving a response from a called substation todisconnect the first of said interrupters from'the circuit of theinterrupter relay and connect in place thereof the secondinterrupter incircuit with the interrupter relay. The speed at which the ringinginterrupter relay was energized and Clo-energized is greatly reduced dueto this se i l-n 478,796.

substitution of this second interrupter, thus permitting longer silentperiods between each application of ringing current which are of shortduration to advise the called subscriber, as before mentioned, that thecalling subscriber no longer-desires connection with the calledsubscriber; ii

In the accompanying drawing I have illustrated a preferred embodiment ofmy invention and the system shown includes calling substation A,terminatingin line circuit L, having the usual line relay LR,

cut-off relay CO and the line jacks J and the multiple line lamps S andto the right of the drawing I show a called substation B terminating aline circuit L having the .usual line relay LR, cut-oft relay CO linejacks J and multiple line lamps S. The line circuits L andL shown areWhat are known as multiple line lamp circuits in which a line lamp S isprovided for each jack, so that when a call is initiated a line signalappears before each ofthe calling line jacks J and any one of aplurality of operators may seize this call to the exclusion of theothers. The cord circuit C illustrated in thedrawing is arranged forinterconnecting the telephone lines A and Bas calling and called linesand comprises answering plug AP and a calling plug GP connected by theheavily marked talking conductors. The answering end of the cord circuitC comprises anianswering tip supervisory relayAT and an answering sleevesupervisory relay AS.

The answering sleeve supervisory relayAS energizing connects theoperators set O to the cord conductors so that she'may be placed incommunication with the" calling subscriber at substation A. Relays ATand AS upon energization also prevent the premature lighting of theanswering super visory lampAL. A high resistance test relay TE is alsoprovided, which relay TE is for the purpose of excluding any otheroperator that may attempt to seize the call after an operator hasalready established connectionto the calling line.' Aj link disconnectrelay LD is also providedwhichis energized when the subscriberata'calling substation replaces his"rece iver upon. the switchhookto'disassociate the cord circuit connected with his line vfrom hisassociated line circuit which will permit the subscriber to recall, ifhe wishes to do so.

The calling end of the cord circuit C comprises the calling tipsupervisory relay CT and the calling sleeve supervisory relay CS, saidrelays CT and CS being for the usual supervisory purposes forcontrolling the calling supervisory lamp. control relay RC is alsoprovided, which relay is energized upon the depression of the ringingkey plunger of the party line ringing key BK, to bring about theenergization of the said relay EC to connect the constantly rotatinginterrupter I in circuit with a ringing interrupter relay R1 tointermittently connect ringing current from one of a plurality ofringing generators G, G, G or G to intermittently actuate the call bellat the called substation B. A meter relay MB is also provided inassociation with the meter magnet MM to register a connection.

Having described in general the apparatus employed in the preferredembodiment of my invention, I will now describe more in detail theoperation of the system as illustrated in the accompanying drawing.

Assuming that the subscriber at the substation A initiates a call, theremoval of the receiver at the substation A establishes an energizingcircuit for the line relay LR and the line relay LR energizing closesits alternate contact 2, whereby the line signals S before the differentassociatedjacks J are lighted. The first operator to seize the call bythe insertion of an answering plug AP into one of the jacks J connectsthe high resistance test relay TE and cut-off relay CO in series, frombattery through the winding of the relay TE, conductor 3, sleevecontacts of the connected plug AP and jack J to ground through thewinding of the cut-ofif relay CO. Relay TE is energized over thiscircuit, and the closing of its alternate contact t connects the lowresistance answering sleeve supervisory-relay AS in series with thecut-off relay CO, the circuit being traced from battery through thewinding of the relay AS, conductors 5 and 6, alternate contact 4 of therelay TE, conductor 3, to ground through the winding of the cut-oilrelay 00, over the previously described path.

The closing of alternate contact 7 of the relay AS connects the windingof the said relay AS directly to the sleeve strand of the cord circuit Cindependent of the contact 4; of the test relay TE and relay AS remainsenergized until disconnection takes place. Due to the flow of currentthrough the windings of the relays AS and TE over the calling line, theanswering tip supervisory relay AT is also energized over the circuittraced from ground through the A ringing winding of relay AT, normalcontact 8 of the link disconnect relay LD, the tip contacts of theconnected plug AP and jack J, through the closed contacts at thesubstation switchhook and back through the sleeve contacts of theconnected jack J and plug A1,

normal contact 9 of the relay LD, conductor 5, alternate contact 7 ol'the relay AS, to battery through the winding of the said relay AS, Therelay AT energizes over this circuit and opens its normal contact 10 toprevent the premature lighting of the answering supervisory lamp AL, andthe opening of its normal contact 11 prevents the premature energizationof the link disconnect relay LD. The closing of alternate contacts 12and 130i the answering sleeve supervisory relay AS connects theoperators set 0 in bridge of the talking conductors of the cord C, overconductors 1a and 15, alternate contacts 12 and 13 of the relay AS,conductors 16 and 17, normal contacts 18 and 19 of the calling sleevesupervisory relay CS, and conductors 20' and 21 to the tip and sleeveconductors of the cord circuit C. Should a second operator insert ananswering plug AP into another jack J of the calling line subsequent tothe insertion of the plug AP of the cord circuit C, the test relay TE ofthis second cord does not energize due to the shunting of its winding bythe low resistance relay ASof the cord circuit C, so that the secondoperator is unable to communicate with the calling subscriber becauseher operators set is not connected due to the failure of the answeringsleeve supervisory relay AS of the second cord to energize, and thesecond operator receiving no response again withdraws the answering plugAP of the second cord from the connected jack. The iirst operator beingconnected with the calling subscriber at substation A, as justdescribed, now inquires the wants of the-calling subscriber thereat-Assuming that it is the subscriber at the substation B that is wanted,the operator tests the jack J of the called line in the usual manner,and, if busy, receives the customary click in her head set. Assumingthat the line is, idle, the operator inserts the 1 calling plug OP intothe jack J of the called line B, thus establishing a series energizingcircuit for the calling sleeve supervisory relay CS and the cut-0E relayC0 of the line circuit L associated with the called substation B, frombattery through the winding of the relay CS, sleeve contacts of theconnected plug UP and jack J, to ground through the winding of thecut-oil relay CO. The'relay CS energizing opens its normal contacts 18and 19 to disconnect the operators set 0 from the cord. The

operator now depresses the proper key plunger of the ringing key BKwhereby the selected frequency generator, which we will assume is G, isconnected to the ringing conductor 22. The actuation of the ringing keyplunger to its fully depressed position also momentarily actuates theend spring contacts 23 and 24. The closing of alternate contact 23 ofthe end spring contacts establishes an energizing circuit for theringing control relay RC, traced from battery through the Winding of therelay RC, conductor 25, alternate contact 23 ot' the end springcont-acts, conductors 26 and 27, to ground at alternate contact 28 ofthe calling sleeve supervisory relay CS. The relay RU energizing closesits alternate contact 529, establishing a locking circuit for itselftraced from battery through its Winding, its alternate contact 29,conductor 30, normal contact 31 of the relay OT, and conductors 32 and27, to ground at alternate contact 28 of the relay CS. The relay. RCenergizing interrupts its normal contacts 33 and 34 to interrupt thetalking strands of the cord, and the closing of its alternate contact 35establishes a circuit for the ringing interrupter relay RI, traced frombattery through the constantly rotating interrupter I. conductor 36,normal contact 37 of the relay LD, conductor 38, through the Winding ofthe ringing interrupter relay RI, conductor 39, alternate contact 35 ofthe relay RU, conductor 40, normal contact 23 01. the end springcontacts, conductors 26 and 27, to ground at alternate contact 28 of therelay CS.

The interrupter I is of the usual type used in connection With automaticringing and its period of interruption is, say for the purpose ofillustration, one second on and four seconds oiflthat is, theinterrupter will energize the relay BI for one second to perznit theapplication of ringing current for one second and permit the relay toremain ale-energized for four seconds, in Which no ringing current willbe transmitted to the called substation.

The momentary closure of alternate contact 24 of the end spring contactsupon the depression of a plunger ot the ringing key BK closes anenergizing circuit for the meter relay MR from battery through thewinding of the relay MR, the closed contact 24 of the end springcontacts, conductor il, normal contact 29 of the relay BC, conductor 30,normal contact 31 of the relay CT, conductors 32 and 27, to ground atalternate contact 28 of the relay CS. The meter relay MR energizing nowcloses its alternate contact to energize the meter magnet MM, whichmeter magnetactuates the meter mechanism.

The ringing interrupter relay RI is intermittently energized over thecircuit just described, and the ringing current to the called substationB may be traced from the gene 'ator G through the now closed ringing keythe relay BI.

Upon the response of the called subscriber at the substation B andfollowing th deenergization of the relay RI, a circuit is establishedfor the calling tip supervisory relay CT, traced from ground through theWinding of the relay CT, normal contact of the relay RI, conductor a3,alternate contact 44; of the relay (is, tip contacts of the connectedplug GP and jack J, through the noW closed contacts at the substationswitchhoolr, back through the sleeve contacts of the connected jack Jand plugC P, to battery through the Winding of the calling sleer'esupervisory relay CS. The relay CT energizing opens its normal contact31, which interrupts the locking circuit for the ringin control relayBC, and the said relay HOW de-energizcs, and theopening of its alternatecontact 35 disconnects the constantly rotating interrupter I from theringing in terrupter relay RI, thus preventing further application ofringing current to the called substation B. The closing of normal coirtacts 38 and 34; of the now de-energized relay RC re-establishes thecontinuity of the talking conductors, and the calling subscrlber at thesubstatlon A and the called subscrlber at the substatlon B are now inconversational circuit, Which may be traced over the heavily markedconductors.

Assuming now that a connection has been extended to the calledsubstation B, as just described, and that the call bell at saidsubstation B is being actuated, but that the calling subscriber at thesubstation A replaces his receiver prior to receiving a response fromthe subscriber at the called substation B, the replacing of the receiverat the calling substation A by the subscriber thereat opens theenergizing circuit of the 115 answering tip supervisory relay AT at theswitchhook contacts, and the closing of its normal contact 11establishes an energizing circuit for the link disconnect relay LD,traced from battery through the winding of the relay LD, conductor 50,normal contact 11 of the relay AT, conductor 51, alternate contact 52 ofthe relay AS, conductors 26 and 27 to ground at alternate contact 28 of195 the relay CS.

The relay LD energizes over this circuit and opens its normal contact 9,interrupting the energizing circuit of the answering sleeve supervisoryrelay AS, but a substitute circuit is established for the said relay AS,traced from battery through the winding of the relay AS, its alternatecontact 7, conductor 3, alternate contact a of the relay TE, conductor 6alternate contact 53 01 the relay Ll), conductors 5a and 51, alternatecontact 52 of the relay AS, conductors 26 and 27, to ground at alternatecontact 28 of the relay CS. The energizing circuit of the relay TE isalso interrupted at normal contact 9, but the relay TE has a substitutecircuit established for it from battery through the winding of the relayTE, its alternate contact l, to ground at alternate contact 28 of therelay CS over the path as just described.

The closing or" normal contact 10 of the answering tip supervisory relayAT establishes a circuit for the answering supervisory lamp AL, tracedfrom battery through the lamp AL, conductor 55, normal contact 10 of therelay AT, conductor 56, alternate contact 57 of the relay AS, conductor58, alternate contact 59 of the relay RC, over conductor 60 to groundthrough the constantly rotating interrupter I. The relay RC is notde-energized as the called subscriber has not answered, and therefore,the calling tip supervisory relay CT is still at normal and the lockingcircuit of the relay ,RC is maintained. The circuit for the answeringsupervisory lamp AL just described includes the rotating interrupter Iand causes the same to flash, indicating to the operator that theconnection needs immediate attention and that she should im mediatelywithdraw the calling plug OP as the calling subscriber at substation Ahas replaced his receiver prior to the response of called subscriber atthe substation B.

The linl: disconnect relay energizing opens its normal contact 37,disconnecting the interrupter I in circuit with the interrupter relayRI, but the closing of alternate contact 37 of the relay Ll) connectsslow speed interrupter E in circuit with the relay R1, traced frombatttery through the slowspeed interriu'iter l conductor 61, alternatecontact 37, conductor 38, through the winding of the ringing interrupterrelay RI, conductor 89, alternate contact of the ringing control relayRC, conductor 40, normal contact 23 of the end spring contacts,conductors 26 and 27, to ground at alternate contact 28 of the sleevesupervisory relay CS.

The interrupter i? that is now substituted in place of the interrupter Iis of slower speed and its period of on and of? may be of any desiredlength, and for illustration, the period during which the ringinginterrupter relay is energized to apply ringing current to the calledline may he oi one sec- 0nd duration, and the period during which therelay Rl remains (lo-energized may be of any desired length, asthirtyseconds.

The ordinary ringing interrupter I having been disconnected from thecircuit with the ringing interrupte relay RI and being now connectedwith the slow-speed interrupter 1 due to the closure o'l alternatecontact 3?, upon the energization ot the link disconnect relay LD, thisconnection pcrinits the ringing interrupter relay to remain dc-energizedfor a longer period of time than when the interruntcr l is connected incircuit, so that only a few applications of ringing current are extendedto the called substation B during the time that the operator receivesthe flashing disconnect signal tron: the answering supervisory lamp Alluntil the time she ren'ioves the cit-tiling ping Cl? from the connectedjack J. Under ordinary circumstances discou nection takes placeimmediately upon receiving the disconnect signal, and ringing current tothe called line after the calling subscriber replaees his receiver willnot be transmitted as the period or time will be very short between thetime that the disconnect signal flashes and the time of the removal ofthe calling plug CP.

The withdrawal of the calling plug CP from the jack =l opens the seriesenergizing circ tor the calling sleeve supervisory relay Cr w and thecut-off relay CO, and the relay (Fa de-energizing opens its alternatecontact 28, opening the locking circuit of the ringing control relay BC.The ringing contrc-l relay PC deenergizing opens its alternate contact59 and disconnects the inter rupter I from the answering supervisorylamp All to prevent further flashing of the said lamp. The relay Ll)will 'de-energize upon the removal of the plug Cl? from the jack J dueto the opening of its circuit at alternate contact 28 of relay CS.Relays TE and AS will also de-energize momentarily due to the opening ofalternate contact 28 of relay CS but will again energize upon theclosure of normal contact 9 of relay LD as a circuit will be closed forthese relays through the now closed contact 9 of relay LD and thewinding of relay CO as described hereinbefore. Should the answering plugAP of another cord circuit be connected to a multiple jack J while therelay LD of cord circuit C is in its energized position, the relays TEand AS de-energizing upon the removal of the plug Cl? from the jack Jwill not again energize upon the closure of normal contact 9 of relayLD, due to the fact that relay AS of the said other cord circuitconnected to one of the jacks J will be energized and will shunt out thehigh resistance relay TE of the cord circuit C, and because of thefailure of said relay TE to energize, relay AS vof cord circuit C willbe prev-nted from energizing thus avoiding any disturbance of theconnection by said other cord circuit.

llu

The operator now withdraws the answer mg plug Al? from the jack J of thecalling line and the apparatus used in establishing subscriber at thesubstation A desires to initiate a. recall immediately atte'r replacinghis receiver upon the switchhoolc and before the removal of the plugs APand from their respective jacks, the removal of the receiver at therecalling substation A; again establishes a circuit for the line relayLR, andthe line relay LR is energized to light the asociated linesignals S so that the same or another operator may take the call.

hen a connection has been established between two subscribers at thesubstations A and B in themanuer as before described, and both receiversare off their switchhooks, the conversational circuit may be traced overthe heavily marked conductors. At the termination of the conversationthe replacing of the receiver at the substation A opens the energizingcircuit of the answer-' ing tip supervisory relay AT, and the relay ATnow restores to close its normal contacts 10 and 11.

The closing of normal contact ll of the relay AT establishes anenergizing circuit for the linlr disconnect relay Ll) over a circuit aspreviously described, and the relay Ll) energizing opens its normalcontacts 8 and 9to interrupt the tip and sleeve cord conductors, and theopening of normal contact 9 opens the series energizing circuit of thecut-off relay CO and the answering sleeve supervisory relay AS, but asubstitute energizing circuit is established for the said relay AS dueto the closure of alternate contact of the relay LD, The relay TE isalso held energized through the alternate contact 53 and thus theanswering supervisory'relay AS and the relay TE remain energized.

The closing of normal contact 10 oi the relay AT establishes anenergizing circuit for the answering supervisory lamp AL, from batterythrough the lamp AL, conductor 55, normal contact 10 of the relay AT,conductor 56, alternate contact 57 of the relay AS, conductor 58, normalcontact 59 of the relay RC, conductors 26 and 27 to ground at alternatecontact 28 of the relay The replacing of the receiver at the calledsubstation B opens the energizing circuit of the calling tip supervisoryrelay CT atv the switchhook contacts, and the relay CT de-energizingcloses its normal contact 31, establishing an energizing circuit for thecalling supervisory lamp CL, traced from battery through the lamp CL,conductor 41', normal contact 29 of the relay RC, conductor 30, normalcontact 31 of the relay GT, conductors 32 and 27 to ground at alternatecontact 280i the relay CS. i

The operator noting the two lightedi line signals AL and CI) nowWithdraws theanswering plug and callingplu'g Cl? All.

from their respective jacks J and J. y The w tl'idrawal otthe plug UPfrom the jack J" opens the energizing circuit of the relay QS,v nd therelayCS restoring opens the circuits of the relays Ll), TE and AS. The

removal of the plug A l? from the jack 'J places the apparatus that wasused in; es-

tablishing the connection at normalgfwhich:

may now be usedffor establishing other con- 7 nections.

lVhile I have illustrated and described my' invention in -connectionwith a preferred form' o't cord: circuit, it" is to" be understood thatit is applicable for use with 1 other circuits than that shownj It will'also be apparentthat changes" and modifications will suggest themselvesby those skilled in the art, and I; therefore, do not Wish to be limitedto the exact structure as shown, but aim to cover all such changes andmodifica tions as come Within the spirit and scope of the appendedclaims.

.Having described my invention what In claim as new and: desire tosecure by United? States Letters Patent is:' t

1. A telephone system. comprising tele-' pnone l1nes', an operators l nkcircuit for".

interconnecting said lines, operator oon-- trolled means 'forapplyingrlngingcurrent to a called line, an interrupter andan inv phonelines, an operators link circuit for interconnecting said lines,operator con trolled means for applying-ringing current and continuingsuchappli'cation to a called line, an interrupter and an interrupterrelay in circuit with said interrupter for in termittently applying saidringing current.)

meansfor interrupting the application of ringing current "by controlexercised at the called line, a secondunterrup'ter, and

second intermeans-under a control exercised by the calling' line fordisconnecting said. first inter rupter and connecting said second interrupter in said circuit.

3. A telephone system including a callfor disconnecting said firstinterrupter and connecting said second interrupter to change theintermittent period of energization and de-energization of saidinterrupter relay prior to a response of the called subscriber.

4. A telephone system including a calling subscribers telephone line anda called subscribers telephone line, an op erators link circuit for usein interconnecting said lines,'a source of ringing current, aninterrupter and an interrupter relay in circuit therewith forvintermittently connecting said ringing current to said calledsubscribers line, control means exercised by the response of said calledsubscriber to disconnect said ringing current, a second interrupter, adisconnect relay under the control'of the calling subscriber todisconnect said first interrupter" and connect in circuit the secondinterrupter when the calling subscriber disconnects prior to theresponse of the called subscriber to change the period of intermittentenergization and deenergization of said interrupter relay.

5. A telephone system including a calling subscribers line and a calledsubscribers line, an operators link circuit for interconnecting saidlines, supervisory relays under the control of the respectivesubscribers and "supervisory lamps controlled by said'relays,

interrupter means connected in circuit with 'Cll'ClHt independently ofsaid switchboard the supervisory lamp under the control of the callingsubscriber when the said subscriber disconnects prior to the response ofthe called subscriber, and automatic means for said link circuit forfreeing the calling subscribers line from said link circuitindependently of the switchboard operator at said link circuit.

6.[A telephone system including a calling subscribers line and a calledsubscribers line, an operators linkcircuit for use in interconnectingsaid lines, supervisory relays under the control of the respectivesubscribers lamps controlled by said relays to give the operator thedisconnect signal when disconnection takes place between calling andcalled lines, an interrupter connected in' circuit with one of saidsupervisory lamps under the control of the calling subscriber when thesaid subscriber disconnects prior to the response of the calledsubscriber to cause and supervisorysupervisory device, means controlledby one subscriber for intermittently operatingsaid device whenhe signalsfor disconnection if the other" subscriber has not responded and forcausing a continuous operation of said device if the othersubscriber hasresponded.

9. A telephone system including 'a' pa'irof lines, a circuit forconnecting said lines, a signal, means controlled by one subscriber forflashing said signal if the other subscrib-.

er has not responded, and means controlled by said other subscriber forafterwards causing a continuous operation, of said signal. v I

10. In a telephone system including a pair of telephone lines, a linkcircuit for interconnecting said lines, a signal for said link circuithaving a steady glow and an intermittent glow for denoting varioussignals to the switchboard operator, means controlled by the callingsubscriber for effecting the operations of said signal, electromagneticmeans for said link circuit for automatically applying ringing currentto the called line of said pair of telephone lines, and means forfreeing said calling line from said link operator, said last meanscontrolling said electromagnetic means.

1.1. A telephone system including a calling and called subscriberslines, a link circuit for interconnecting said lines, a signal having asteady glow and an intermittent glow for denoting different connectionconditions to the switchboard operator, electromagnetic means for saidlink circuit tor'automatically applying ringing current to the calledline of said pair of telephone lines, and automatic means for freeingthe calling line from the link circuit to permit said calling subscriberto recall prior to the disconnection of said link circuit and callingsubscribers line, said last means: controlling said electromagneticmeans. i

Signed by me at Chicago, in the county of Cook and StateOfIlliIiOiS,tl1iS 17th; day of June, 1921.

GEORGE A. YANOCHOWSKI

